Axial turbo-expander design for organic Rankine cycle waste-heat recovery with comparative heavy-duty diesel engine drive-cycle performance assessment

Despite the high thermal efficiency achieved by modern heavy-duty diesel engines, over 40% of the energy contained in the fuel is wasted as heat either in the cooling or the exhaust gases. By recovering part of the wasted energy, the overall thermal efficiency of the engine increases and the pollutant emissions are reduced. Organic Rankine cycle (ORC) systems are considered a favourable candidate technology to recover exhaust gas waste heat, because of their simplicity and small backpressure impact on the engine performance and fuel consumption. The recovered energy can be transformed into electricity or directly into mechanical power. In this study, an axial turbine expander for an ORC system was designed and optimized for a heavy-duty diesel engine for which real-world data were available. The impact of the ORC system on the fuel consumption under various operating points was investigated. Compared to an ORC system equipped with a radial turbine expander, the axial design improved fuel consumption by between 2 and 10% at low and high engine speeds. Finally, the benefits of utilising ORC systems for waste heat recovery in heavy-duty trucks is evaluated by performing various drive cycle tests, and it is found that the highest values of fuel consumption were found in the NEDC and the HDUDDS as these cycles generally involve more dynamic driving profiles. However, it was in these cycles that the ORC could recover more energy with an overall fuel consumption reduction of 5 and 4.8%, respectively

Diesel Spray Liquid Length Imaging at High Pressure

Data Availability Statement: Data available upon request at [email protected] © 2023 by the authors. Engine efficiency and emissions depend on the fuel atomization and dispersion. The fuel atomization and dispersion depend heavily on the ambient pressure and temperature. In this work, to study Diesel sprays in engine conditions, an electrically heated, constant-volume, pressurized vessel was designed and manufactured. The controlling electronics and software were developed and tested to ensure safe and precise operation. A commercial Bosch six-hole automotive Diesel injector was used. The spray spatial and temporal development were studied. In the literature, spray liquid length and cone angle are extensively used to quantify fuel dispersion. In this work, these parameters were quantified using a high-speed shadowgraph technique. Models were derived to describe the temporal evolution of the liquid core. Such models can be used to predict the Diesel spray behaviour and the engine performance.This research received no external funding

Investigation of the temporal behavior of desiccant disk for use in dehumidifiers and air conditioners

Data availability: Data will be made available on request.The majority of household energy is consumed in heating and air conditioning. Desiccant disks are a way to harvest renewable solar energy or waste heat for air conditioning. In the literature there is a gap in the investigation of start-up of desiccant dehumidifiers, which this paper attempts to covers. For this work, a desiccant disk was designed, manufactured, and tested. To reduce the cost, off-the-shelf components were used as structure materials. And as adsorption material, widely available materials were used. Input heat was simulated by an electrical heater and power to auxiliary motors was provided in the form of DC power. Temperature and humidity were recorded at various locations using DHT11 sensors. The system was turned off and tested at a start of operation mode. The performance of the desiccant disk was quantified by the coefficient of performance and the dehumidification efficiency. Results showed gradual increase of the desiccant disk efficiency with a maximum COP value of 0.4 reached within 10 min of the start of operation. Time delays were attributed to heating of the disk. Further work is required to fully understand the transient operation

Using XDAQ in Application Scenarios of the CMS Experiment

XDAQ is a generic data acquisition software environment that emerged from a rich set of of use-cases encountered in the CMS experiment. They cover not the deployment for multiple sub-detectors and the operation of different processing and networking equipment as well as a distributed collaboration of users with different needs. The use of the software in various application scenarios demonstrated the viability of the approach. We discuss two applications, the tracker local DAQ system for front-end commissioning and the muon chamber validation system. The description is completed by a brief overview of XDAQ.Comment: Conference CHEP 2003 (Computing in High Energy and Nuclear Physics, La Jolla, CA

The CMS Event Builder

The data acquisition system of the CMS experiment at the Large Hadron Collider will employ an event builder which will combine data from about 500 data sources into full events at an aggregate throughput of 100 GByte/s. Several architectures and switch technologies have been evaluated for the DAQ Technical Design Report by measurements with test benches and by simulation. This paper describes studies of an EVB test-bench based on 64 PCs acting as data sources and data consumers and employing both Gigabit Ethernet and Myrinet technologies as the interconnect. In the case of Ethernet, protocols based on Layer-2 frames and on TCP/IP are evaluated. Results from ongoing studies, including measurements on throughput and scaling are presented. The architecture of the baseline CMS event builder will be outlined. The event builder is organised into two stages with intelligent buffers in between. The first stage contains 64 switches performing a first level of data concentration by building super-fragments from fragments of 8 data sources. The second stage combines the 64 super-fragments into full events. This architecture allows installation of the second stage of the event builder in steps, with the overall throughput scaling linearly with the number of switches in the second stage. Possible implementations of the components of the event builder are discussed and the expected performance of the full event builder is outlined.Comment: Conference CHEP0

Axial Turbo-Expander Design for Organic Rankine Cycle Waste-Heat Recovery With Comparative Heavy-Duty Diesel Engine Drive-Cycle Performance Assessment

Data Availability Statement: The datasets presented in this article are not readily available because of commercial reasons. Requests to access the datasets should be directed to Brunel University [email protected] the high thermal efficiency achieved by modern heavy-duty diesel engines, over 40% of the energy contained in the fuel is wasted as heat either in the cooling or the exhaust gases. By recovering part of the wasted energy, the overall thermal efficiency of the engine increases and the pollutant emissions are reduced. Organic Rankine cycle (ORC) systems are considered a favourable candidate technology to recover exhaust gas waste heat, because of their simplicity and small backpressure impact on the engine performance and fuel consumption. The recovered energy can be transformed into electricity or directly into mechanical power. In this study, an axial turbine expander for an ORC system was designed and optimized for a heavy-duty diesel engine for which real-world data were available. The impact of the ORC system on the fuel consumption under various operating points was investigated. Compared to an ORC system equipped with a radial turbine expander, the axial design improved fuel consumption by between 2 and 10% at low and high engine speeds. Finally, the benefits of utilising ORC systems for waste heat recovery in heavy-duty trucks is evaluated by performing various drive cycle tests, and it is found that the highest values of fuel consumption were found in the NEDC and the HDUDDS as these cycles generally involve more dynamic driving profiles. However, it was in these cycles that the ORC could recover more energy with an overall fuel consumption reduction of 5 and 4.8%, respectively

Electric Vehicle Modelling for Future Technology and Market Penetration Analysis

Data Availability Statement: The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author.The transportation sector is generally thought to be contributing up to 25% of all greenhouse gases (GHG) emissions globally. Hence, reducing the usage of fossil fuels by the introduction of electrified powertrain technologies such as hybrid electric vehicle (HEV), battery electric vehicle (BEV) and Fuel Cell Electric Vehicle (FCEV) is perceived as a way towards a more sustainable future. With a seemingly more significant shift towards BEV development and roll-out, the research and development of BEV technologies has taken on increasing importance in improving BEV performance and ensuring its competitiveness. Numerical simulation, using MATLAB, is performed as a tool to investigate and to improve the overall performance of BEVs. This study provides an overview of the possible technology outcome and market consequences for future compact BEVs along with HEVs, FCEVs and internal combustion engine vehicles (ICEV). The techno-economics of BEVs, market projection and cost analysis up to 2050 are investigated, as are important BEV characteristics alongside those of other types of vehicles. Well-to-wheel analysis of BEVs is also studied and compared with HEV, FCEV and ICE

Measurement of J/Psi and Psi(2S) Polarization in ppbar Collisions at sqrt(s) = 1.8 TeV

We have measured the polarization of J/Psi and Psi(2S) mesons produced in p\bar{p} collisions at \sqrt{s} = 1.8 TeV, using data collected at CDF during 1992-95. The polarization of promptly produced J/Psi [Psi(2S)] mesons is isolated from those produced in B-hadron decay, and measured over the kinematic range 4[5.5] < P_T < 20 GeV/c and |y| < 0.6. For P_T \gessim 12 GeV/c we do not observe significant polarization in the prompt component.Comment: Revised version, accepted for publication in Physical Review Letter